[OT] Some strange mails from owner-postfix-users@postfix.org

Hi all:

The lastest two days i have received some strange mails which sent from
owner-postfix-users@postfix.org.
Each of them has no 'Subject' and 'To' with a body
"aaazzzaaazzzaaazzzaaazzzaaazzz".

And the handerlines are follow:

___________________________________BEGIN__________ ________________________
Return-Path: <owner-postfix-users@postfix.org>
Received: from hackles.realss.com ([unix socket])
by mail.eoa.cn (Cyrus v2.2.3-Gentoo) with LMTP; Wed, 06 Oct 2004 15:16:42 +0800
X-Sieve: CMU Sieve 2.2
Received: from camomile.cloud9.net (camomile.cloud9.net [168.100.1.3])
by hackles.realss.com (Postfix) with ESMTP id CC584500E1
for <wangpenghui@realss.com>; Wed, 6 Oct 2004 15:16:41 +0800 (CST)
Message-Id: <20041006071641.CC584500E1@hackles.realss.com>
Date: Wed, 6 Oct 2004 15:16:41 +0800 (CST)
From: owner-postfix-users@postfix.org
To: undisclosed-recipients:;

aaazzzaaazzzaaazzzaaazzzaaazzz

____________________________________END___________ __________________________

Could someone pick me up with this letter.
Thank you in advance!

Wang Penghui